Drainage and grading for Edmonton asphalt, water first
If one thing on this site deserves more attention than it gets, it is this. Where water goes decides how long a surface lasts, and it is designed before any asphalt is ordered or it is not designed at all.
Asphalt is not harmed much by water running across it. It is harmed by water sitting on it, because standing water finds its way through the surface and into the base, and a wet base under traffic stops being a base.
That makes fall the most important dimension on a paving job. Too little and water pools in the flat spots; enough and the surface clears itself after every rainfall without anyone thinking about it.
The second half is where the water ends up. A fall that moves water to a corner with no outlet has relocated the problem rather than solved it, which is why correcting ponding is usually about the destination, the base has to be shaped before the surface, and service life follows from both.
Sheds water
How it is designed
How Edmonton grading is worked out
Find out where water comes from
Roof runoff, a sloping lawn and the road itself all add water to a surface. A design that only considers rain falling directly on it is incomplete.
Identify where it can go
A drain, a swale, a lawn or a kerb line. This is decided before the fall is set, because the fall has to point at something.
Shape the base, not just the surface
The grade is built into the base and the asphalt follows it. Trying to create fall with varying asphalt thickness gives you a surface that wears unevenly.
Check it with water
The real test is rain, or a hose. A surface that looks right and still holds water in one spot needs that spot addressed before anybody signs it off.
Fixing it later
Correcting drainage on existing Edmonton asphalt
On an existing surface the options depend on how much has to change. A small low area can often be cut out and rebuilt to the right level, which is a contained piece of work.
A whole surface that drains the wrong way is a bigger conversation. Overlaying to create fall adds height, and that has to work with doors, garages and the road, so it is not always available as an answer.
Sometimes the honest fix is outside the asphalt entirely: a drain added, a swale cut, or a downspout redirected away from the surface. That work sits alongside levelling settled areas, and on a lot a ranked plan puts drainage ahead of resurfacing for exactly this reason.
Enough that water visibly moves and nothing stands after rain. The exact figure depends on the site, but the test is simple: go out in the wet and look.
Not if you want it to last. A flat surface holds water in every slight imperfection, and those become the first places the base gets wet and the asphalt fails.
Somewhere identified before the fall is set: a drain, a swale, a lawn or a kerb line. A slope pointing at a corner with no outlet has only moved the problem.
Often yes. A contained low area can be cut out and rebuilt to level, and sometimes the real answer is a new drain or a redirected downspout rather than asphalt work at all.
Because fall built from varying asphalt thickness wears unevenly, and added height has to work with doors, garages and the road. The grade belongs in the base.
A great deal. A downspout discharging onto a driveway puts far more water on one spot than rainfall does, and redirecting it is often the simplest improvement available.
Get Edmonton drainage looked at before the surface is laid
We will work out where water comes from, where it can go, and build the fall into the base so the surface clears itself without anyone thinking about it.
